Here is a list of some leading national suppliers of welded parts to specification in the United Kingdom:

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Leading Suppliers of Welded Parts to Specification in the UK

1. Stainless Fabrications Ltd

   • Specializes in stainless steel welded components and fabrications.

2. Weld-Tech Limited

   • Offers a range of welding services and custom metal fabrications.

3. K.T. Fabrications Ltd

   • Focuses on metal fabrications and provides tailored welded parts.

4. Lloyds Metal Works

   • Provides comprehensive welding and fabrication services for various industries.

5. Bramley Engineering

   • Known for precision engineering and bespoke welded assemblies.

6. D.H. Stainless Fabrications Ltd

   • Experts in stainless steel welding and fabrication for various applications.

7. A-Metric Engineering Ltd

   • Offers construction and installation of welded components and structural steel.

8. Medway Welding

   • Specializes in heavy-duty welded components and custom fabrications.

9. Alton Welding & Engineering Co Ltd

   • Provides a variety of welding services, including MIG and TIG welding.

10. Steelcraft Ltd

    • Delivers steel fabrications and specialized welded products for multiple sectors. ```

This list includes a mix of companies that provide various welding services and custom parts fabrication across different industries in the UK. For more detailed evaluations, reviewing each company's capabilities, certifications, and client work may be beneficial.